1. Field of the Invention
The present invention relates in general to a heating and cooling device, and more particularly to an absorption heating and cooling device for heating and cooling the room by heating lithium bromide solution.
2. Description of the Prior Art
There have been proposed several types of absorption heating and cooling devices such as disclosed in Japanese Patent Publication No. Heisei. 4-56227, Japanese Patent Laid-open Publication No. Heisei. 3-199864 and Japanese Patent Publication No. Heisei. 2-22872.
With reference to FIG. 12. there is shown an absorption heating and cooling device disclosed in Japanese Patent Publication No. Heisei 4-56227. This heating and cooling device maintains the inner pressure of its evaporator 201 at about 1/100 atm. In this device, the refrigerant liquid is sprayed by a refrigerant pump 202 to a heat transfer pipe, through which the cool water 203 passes, thus to absorb the heat from the cool water in the heat transfer pipe and to achieve a desired cooling effect. The evaporated refrigerant gas is supplied to an absorption unit 205 which is maintained at a lower pressure by the cooling water 204 and in which the refrigerant gas is absorbed into lithium bromide solution sprayed by a solution pump 206, thus to dilute the lithium bromide solution in order to make lithium bromide dilute solution. Part of the lithium bromide dilute solution is in turn introduced into a high temperature regenerator 208 through a heat exchanger 207 by the solution pump 206 and divided, in the regenerator 208, into directly heated gas and concentrated solution. On the other hand, the remainder of the lithium bromide dilute solution is introduced into a low temperature regenerator 209 and heated in the regenerator 209 by the gas generated by the high temperature regenerator 208 in order to be divided into gas and concentrated solution. The concentrated solution of the regenerators 208 and 209 are in turn introduced into the absorption unit 205 through the heat exchanger 207. A condensed drain resulting from heating of the lithium bromide solution in the low temperature regenerator 209 is introduced into a condenser 210. In addition, the gas generated by the low temperature regenerator 209 is condensed in the condenser 210.
The condensed refrigerant is in turn introduced into the evaporator 201, thus to accomplish one cooling cycle. Here, the condensed refrigerant received by the evaporator 201 is sprayed by a first spray nozzle 211 and the solution of the absorption unit 205 is sprayed by a second spray nozzle 212.
However, in the aforementioned absorption heating and cooling device, the time for heat exchanging between the cool water and the refrigerant circulated in the evaporator is relatively short and the heat transfer area is relatively small, so that it is difficult to improve the heat exchanging efficiency and the refrigerant evaporating efficiency of the device. In addition, it is very difficult to evenly supply the refrigerant to the surface of the evaporator, thus to cause the refrigerant to be only partially evaporated on a part of the heat exchanger.